Btw any recommendation for characters for Base Defense? The last 3 stages have so much beefy enemies that I can't manage to finish under the time limit.
Based on "Clear unit", most people clear it with a team that consists of:
-One tank/frontliner (Hoshino, Tsurugi, Reisa) (I personally used Tsubaki, but she doesn't really contribute damage while those three all do AoE and have self-sustain.)
-Three AoE DPS (Nonomi, Momoi/Midori*, Junko, Hasumi(Swimsuit), Iori, Yukari(Swimsuit), Cherino, Marina
Specials have surprising amount of variance
-Special attack buffers (Fuuka(New Year), Kisaki, Rio)
-Stat stick for Cost Recovery (Shiroko(Swimsuit), Himari) (Shiroko's EX is bit useless, maybe you can slap one of the tougher enemies? Himari's is a simple ATK buff with short duration. Cost recovery is probably the main selling point for either of them.)
-Utaha (her Eleph is available on PvP shop, her turrets can do suprising amount of damage when placed behind the tank)
-Serina (move tank forward so enemies form a nice clump)
-One exceptional individual used Makoto
There are some unconventional picks like Mika (she's single-target nuke, but has fast attack speed and has at least a minor AoE component in her Normal Skill) and Hanako (Swimsuit), who doesn't have a matching attack type but can serve as brute force if you happen to have her.
Kokona is a semi-occurring pick. My guess is that if you need to bring a dedicated healer to Wave Defence, you're doing something wrong. But if you happen to already have her, probably worth trying to make formation with her. At least one clear was presumably based on Kokona keeping Mika alive.
(*A package deal because presence of one twin buffs the other. I don't necessarily recommend it, but I ended up burning my Archive Recruitment tickets on Midori.)